iot_mqtt_protocol.h File Reference

This file contains MQTT 3.1.1 specific defines. This is a common header to be included for building a single threaded light-weight MQTT client as well as stateful CSDK MQTT library. More...

Go to the source code of this file.

Macros
#define	MQTT_PACKET_TYPE_CONNECT   ( ( uint8_t ) 0x10U )
	CONNECT (client-to-server).
#define	MQTT_PACKET_TYPE_CONNACK   ( ( uint8_t ) 0x20U )
	CONNACK (server-to-client).
#define	MQTT_PACKET_TYPE_PUBLISH   ( ( uint8_t ) 0x30U )
	PUBLISH (bidirectional).
#define	MQTT_PACKET_TYPE_PUBACK   ( ( uint8_t ) 0x40U )
	PUBACK (server-to-client).
#define	MQTT_PACKET_TYPE_SUBSCRIBE   ( ( uint8_t ) 0x82U )
	SUBSCRIBE (client-to-server).
#define	MQTT_PACKET_TYPE_SUBACK   ( ( uint8_t ) 0x90U )
	SUBACK (server-to-client).
#define	MQTT_PACKET_TYPE_UNSUBSCRIBE   ( ( uint8_t ) 0xa2U )
	UNSUBSCRIBE (client-to-server).
#define	MQTT_PACKET_TYPE_UNSUBACK   ( ( uint8_t ) 0xb0U )
	UNSUBACK (server-to-client).
#define	MQTT_PACKET_TYPE_PINGREQ   ( ( uint8_t ) 0xc0U )
	PINGREQ (client-to-server).
#define	MQTT_PACKET_TYPE_PINGRESP   ( ( uint8_t ) 0xd0U )
	PINGRESP (server-to-client).
#define	MQTT_PACKET_TYPE_DISCONNECT   ( ( uint8_t ) 0xe0U )
	DISCONNECT (client-to-server).
#define	MQTT_CONNECT_FLAG_CLEAN   ( 1 )
	Clean session.
#define	MQTT_CONNECT_FLAG_WILL   ( 2 )
	Will present.
#define	MQTT_CONNECT_FLAG_WILL_QOS1   ( 3 )
	Will QoS1.
#define	MQTT_CONNECT_FLAG_WILL_QOS2   ( 4 )
	Will QoS2.
#define	MQTT_CONNECT_FLAG_WILL_RETAIN   ( 5 )
	Will retain.
#define	MQTT_CONNECT_FLAG_PASSWORD   ( 6 )
	Password present.
#define	MQTT_CONNECT_FLAG_USERNAME   ( 7 )
	Username present.
#define	MQTT_PUBLISH_FLAG_RETAIN   ( 0 )
	Message retain flag.
#define	MQTT_PUBLISH_FLAG_QOS1   ( 1 )
	Publish QoS 1.
#define	MQTT_PUBLISH_FLAG_QOS2   ( 2 )
	Publish QoS 2.
#define	MQTT_PUBLISH_FLAG_DUP   ( 3 )
	Duplicate message.
#define	MQTT_REMAINING_LENGTH_INVALID   ( ( size_t ) 268435456 )
	A value that represents an invalid remaining length. More...
#define	MQTT_PACKET_CONNECT_MAX_SIZE   ( 327700UL )
	The maximum possible size of a CONNECT packet. More...
#define	MQTT_MIN_PUBLISH_REMAINING_LENGTH_QOS0   ( 3U )
	The minimum remaining length for a QoS 0 PUBLISH. More...
#define	MQTT_MAX_REMAINING_LENGTH   ( 268435455UL )
	Per the MQTT 3.1.1 spec, the largest "Remaining Length" of an MQTT packet is this value.
#define	MQTT_VERSION_3_1_1   ( ( uint8_t ) 4U )
	The constant specifying MQTT version 3.1.1. Placed in the CONNECT packet.
#define	MQTT_PACKET_CONNACK_REMAINING_LENGTH   ( ( uint8_t ) 2U )
	A CONNACK packet always has a "Remaining length" of 2.
#define	MQTT_PACKET_CONNACK_SESSION_PRESENT_MASK   ( ( uint8_t ) 0x01U )
	The "Session Present" bit is always the lowest bit.
#define	MQTT_PACKET_PUBACK_SIZE   ( 4U )
	A PUBACK packet is always 4 bytes in size.
#define	MQTT_PACKET_PUBACK_REMAINING_LENGTH   ( ( uint8_t ) 2 )
	A PUBACK packet always has a "Remaining length" of 2.
#define	MQTT_PACKET_SUBACK_MINIMUM_SIZE   ( 5U )
	The size of the smallest valid SUBACK packet.
#define	MQTT_PACKET_UNSUBACK_REMAINING_LENGTH   ( ( uint8_t ) 2 )
	An UNSUBACK packet always has a "Remaining length" of 2.
#define	MQTT_PACKET_PINGREQ_SIZE   ( 2U )
	A PINGREQ packet is always 2 bytes in size.
#define	MQTT_PACKET_PINGRESP_REMAINING_LENGTH   ( 0U )
	A PINGRESP packet always has a "Remaining length" of 0.
#define	MQTT_PACKET_DISCONNECT_SIZE   ( 2U )
	A DISCONNECT packet is always 2 bytes in size.

Detailed Description

This file contains MQTT 3.1.1 specific defines. This is a common header to be included for building a single threaded light-weight MQTT client as well as stateful CSDK MQTT library.

Macro Definition Documentation

MQTT_REMAINING_LENGTH_INVALID

#define MQTT_REMAINING_LENGTH_INVALID   ( ( size_t ) 268435456 )

A value that represents an invalid remaining length.

This value is greater than what is allowed by the MQTT specification.

MQTT_PACKET_CONNECT_MAX_SIZE

#define MQTT_PACKET_CONNECT_MAX_SIZE   ( 327700UL )

The maximum possible size of a CONNECT packet.

All strings in a CONNECT packet are constrained to 2-byte lengths, giving a maximum length smaller than the max "Remaining Length" constant above.

MQTT_MIN_PUBLISH_REMAINING_LENGTH_QOS0

#define MQTT_MIN_PUBLISH_REMAINING_LENGTH_QOS0   ( 3U )

The minimum remaining length for a QoS 0 PUBLISH.

Includes two bytes for topic name length and one byte for topic name.